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1.
This paper presents an empirical case study about farmer management of rice genetic resources in two communities of Nepal, drawing on interdisciplinary, participatory research that involved farmers, rice geneticists and social scientists. The decision‐making process of farm households is modelled and estimated in order to provide information for the design of community‐based conservation programmes. A bivariate model with sample selection examines the simultaneous process of whether farmers decide to plant landraces or modern varieties, and whether the landraces they choose to plant constitute the genetic diversity of interest for future crop improvement. Findings show that the two landrace choices are affected by different social and economic factors, but in certain cases the decision processes are interrelated. Policies to promote the conservation of local rice diversity will need to take both processes into account.  相似文献   

2.
分析了都江堰市生物多样性的特点、保护现状及存在问题;认为种类丰富、特有种多、显示度高是其物种多样性特点;物种的吉毒性和珍稀濒危性是其遗传多样性特点;类型多样、结构复杂则体现了生态系统多样性特点;目前,全市已成功开展了生物多样性的就地与迁地保护。但在保护区管理与人类活动的影响方面仍存在不少问题;提出了加强宣传教育、加大监测力度,促进科学研究、加强地方立法与执法和加强国际合作与交流等生物多样性保护的对策措施。  相似文献   

3.
Tree species richness, diversity index, standing biomass and biomass carbon stocks were estimated in six villages located under three agro-ecological zones, namely, coastal, hill and plains of Uttara Kannada district, Western Ghats, Peninsular India. The study showed that land use categories other than forest support higher tree species diversity. High basal area, standing biomass and carbon stock in non-forest land categories indicates their potential as carbon sinks and for promotion of species diversity. Inclusion of other non-forest land use categories in afforestation programmes for promotion of multipurpose tree species for conservation of diversity and for enhancing carbon sinks is suggested. There is a need to promote synergy between biodiversity conservation and carbon sequestration under carbon mitigation projects.  相似文献   

4.
Book review     
Smallholder farmers who grow diverse landraces in centres of crop diversity contribute to sustaining the capacity of agricultural and food systems to adapt to change by maintaining crop evolution in their fields today, thus enabling humanity to continue to have the broad genetic variation needed to adapt crops to changes tomorrow. Given this fact, the last 20 years have witnessed an ever-growing interest in on-farm conservation of crop infra-specific diversity. While numerous projects to support it have been, and continue to be, implemented worldwide, there has been very little systematic assessment of the extent to which these projects have been effective at contributing to the maintenance of crop diversity on-farm and the creation of associated benefits for the farmers involved. The factors and relationships implicated in attaining conservation and livelihood results are complex, so that a conceptual scheme that brings them together in a simplified but coherent fashion can be extremely useful for the scientists, donors, policy-makers and practitioners concerned. This paper presents a conceptual framework for analysing on-farm projects, the trade-offs involved and assesses their success in a more systematic way.  相似文献   

5.
Livestock diversity provides genetic alternatives that facilitate sustainable agricultural development. Despite this, animal genetic resources (AnGR) are being depleted at alarming rates. Subsidises available to production systems based on imported breeds are of several orders of magnitude greater than the costs of local breed conservation. Economic arguments for the conservation and sustainable use of threatened AnGR can be an effective means of establishing support for the development of appropriate enabling environments. Despite the importance of the economics of AnGR conservation, the subject has received limited attention. Reasons include: methodological difficulties inherent in valuing genetic resources; limited knowledge about appropriate analytical techniques; and lack of data regarding local breeds. As recent advances in economic valuation have eased methodological/analytical constraints, the issue of data availability has become critical. Data related to livestock keepers' preferences for different genetic resource attributes and the value placed on these across species, breeds and production systems are needed. Based on a study of a local pig breed in Mexico, this paper shows how the use of rural appraisal methods, in conjunction with recently developed analytical techniques, are capable of providing the data required for understanding the type and costs of interventions necessary to promote the conservation and sustainable use of AnGR.  相似文献   

6.
Genetic resources for food and agriculture are the biological basis of world food and nutrition security; and they directly or indirectly support the livelihoods of over 2.5 billion people. Genetic diversity gives a species or a population the ability to adapt to changing environments. For resource-poor farmers, adaptive animal breeds, crop varieties and cultivars adapted to particular micro-niches, stresses or uses are the main resources available to maintain or increase production and provide a secure livelihood. The economic value of genetic diversity for productivity and yield traits is discussed in the literature. However, it is difficult to value many other aspects of agricultural biodiversity as these have both direct and indirect values in terms of qualitative traits such as food, nutrition and environmental uses that include adaptation to low input conditions, co-adaptive complexes, yield stability and the consequent reduction of risk, specific niche adaptation, and in meeting socio-cultural needs. Together, the direct and indirect values of genetic resources for resource-poor farmers are expressed in a range of options in the form of the crop varieties and species they use for managing changing environments.

The value of genetic diversity to resource-poor farmers is seldom captured by markets or addressed by the international research agenda. This paper presents lessons learned from our work over 5–10 years in the Asia and Pacific Ocean (APO) region on participatory crop improvement, home gardens and on-farm management of agricultural biodiversity. The lessons illustrate how farmers adapt genetic resources to suit local environmental conditions. The paper focuses on the value of genetic diversity of selected crop species to meet people's food and other needs. Genetic diversity valued by resource-poor farmers is often maintained, selected and exchanged by local social seed networks. Identification of such genetic resources and their custodians is important if international agricultural research is to contribute to the reduction of poverty. The paper highlights some good practices from case studies that illustrate how such genetic resources could be exploited by informal research and development strategies or participatory plant breeding or for marketing value-added products.  相似文献   

7.
We consider the choice of farm animal breeds for conservationprogrammes. An expert survey among breed societies and scientistsand the analysis of past decisions in EU member countries toenter breeds into conservation programmes show differences inthe valuation of breed characteristics. Whereas both sets ofactors value diversity aspects as well as cultural and economicaspects of breed conservation, policy makers, in comparisonwith experts, seem to be less concerned about true extinctionrisk. The results suggest broadening the discussion about theconservation of animal genetic resources to aspects preservingsocietal and cultural resources.  相似文献   

8.
This paper presents an assessment of the linkages between cropgenetic diversity, farm productivity and risk management. Aflexible moment-based approach is used to analyse the impactof crop genetic diversity on the mean, variance and skewnessof yield. Using farm-level data from Sicily (Italy), econometricevidence shows how crop genetic diversity can increase farmproductivity and reduce risk exposure. The empirical resultsindicate that crop genetic diversity can reduce variance, butonly if pesticide use is low. Furthermore, high diversity levelscan reduce downside risk exposure (e.g. the risk of crop failure).This provides useful insights on the linkages between resilienceand crop genetic diversity.  相似文献   

9.
A variety of public policies and private strategies have been implemented to stimulate farmers to implement nature conservation measures. Examples include publicly funded agri-environment schemes (AES) but also eco-labels and Alternative Food Networks; strategies that have been implemented in response to the continuous decline in species abundance and diversity due to agricultural intensification and scale enlargement. Whereas AES as a distinct governance strategy has been evaluated in detail, less is known about other strategies. In this paper, we assess the relative importance of the variety of public and private strategies aimed at enhancing species abundance and diversity in Italian olive farming through a reduction in agrochemical use. In a survey of olive farmers in the region of Tuscany, we found that although farmers are exposed to a variety of public and private strategies, personal motives to reduce agrochemical use are most important. Moreover, having a Corporate Social Responsibility plan or engaging in direct sales to consumers are the only strategies that are related to a reduction in agrochemical use. These findings suggest self-governance is a powerful strategy for enhancing species diversity and abundance in agricultural landscapes. Yet it also means contributing to nature conservation and restoration is a voluntary act. Olive farmers who do not voluntarily contribute to nature conservation by reducing agrochemicals need to be incentivized by show-casing farmers who did reduce their agrochemical use, by critical consumers or by stricter rules in AES or in generic agri-environmental legislation.  相似文献   

10.
大仓鼠种群生物多样性研究   总被引:2,自引:0,他引:2  
大仓鼠是严重危害我国农业生产的一种害鼠,主要分布于长江以北的广大地区,可分为5个亚种;通过对大仓鼠地理种群、生态和遗传多样性的研究,初步确定了其种群的多样性特征,以期为其种群暴发生物学机制的揭示及对农业害鼠综合治理措施的制订奠定基础。  相似文献   

11.
The world–wide capacity of genebanks for ex situ conservation of crop genetic resources has increased greatly since the 1970s, improving the access of crop breeders to landraces and wild and weedy relatives. But utilization of genebank resources has not kept pace. The set of popular cultivars in major crops is typically rather small, and their ancestry encompasses only a fraction of the genetic diversity currently available in other cultivars. Discussions of farmers' rights that focus on compensation for current incorporation of farmers' varieties in new cultivars have diverted attention from the question of why so little of the newly accessible genetic diversity is currently being utilized by public and private breeders. To optimize the future provision of genebank services, research is needed on the costs of genebanks, the market for their services, the use of genetic resources by breeders, and the implications of recognition of farmers' rights, evolving intellectual property rights, continued funding problems and developments in biotechnology.  相似文献   

12.
安徽省生物多样性的保护   总被引:4,自引:0,他引:4  
安徽省地处亚热带与暖温带的过渡区,是多种动植物区系成分的交汇之地。境内生物丰富,珍稀涉危物种比较多,在分析安徽省物种多样性主要特征地基础上,着重探讨了生物多样性保护的对策问题。  相似文献   

13.
This paper describes a participatory framework used in Alta Verapaz, Guatemala to analyze the future viability of different conservation measures in a cloud forest area. It presents how in the case of conservation initiatives, participatory developed instruments could provide the incentive for farmers to reinforce or introduce conservation measures in their farming systems to preserve habitats, reduce species disruptions and alleviate poverty. A model's architecture was created with stakeholders of different settings of the region of study. Together, baseline-scenarios and policy-scenarios on land use and income generation were developed. The paper investigates the potential impacts of different policy measures for conservation and poverty reduction through the instrument “payments for environmental services”. Aim was to integrate social, economic and environmental aspects.  相似文献   

14.
泉州市野生花卉植物资源研究   总被引:4,自引:0,他引:4  
泉州市有野生花卉植物104种,隶属于55科83属;有重要观赏价值的大约66种,观叶类43种。观花类23种;就资源植物 如何持续利用问题提出几点建议。  相似文献   

15.
Biodiversity conservation planning must be ecosystem-specific and take into account human needs as food production. The Pampa biome is a temperate grassland with high species richness and with an important role in food production in South America. Here we present the first formal Systematic Conservation Planning for the Brazilian part of the Pampa, which is the least protected biome in Brazil. We aimed to build conservation scenarios where at least 17 % of the biome area were protected, following the 11th Aichi target for terrestrial lands protection according to the Convention on Biological Diversity. Our conservation targets were the vegetation types of this biome. Three scenarios were built varying in their proportions of strict protection (SP) and sustainable use areas (SU): Permissive scenario (5 % SP, 12 % SU); Intermediate scenario (10 % SP, 7 % SU) and Restrictive scenario (15 % SP, 2 % SU). Urban and rural areas, as well as bovine and ovine density, were used as prioritization costs, aiming to minimize possible conservation conflicts. Four main clusters of priority areas to protect the vegetational diversity can be observed in all scenarios and should be considered when implementing future protected areas in this threatened biome. Sustainable use areas are suitable for low-density livestock raising, combining biodiversity protection and food production, but strictly protected areas are still important to species most affected by livestock. The combination of strict protection and sustainable use areas can be effective in similar biomes. It should be considered in future international negotiations, such as the 2020 Conference to be held in Beijing, opening new strategies to achieve the 17 % of land protection. We expect that this Systematic Conservation Planning reinforces the recently started scientific discussion regarding the conservation of non-forest ecosystems in Brazil.  相似文献   

16.
[目的]人工造林对生物多样性恢复和城市森林功能发挥的影响深远,科学评估人工造林对生态系统恢复速度及稳定性的影响是实现生物多样性保护的基础。[方法]采用格网法获取北京浅山区276个样本单元,根据2010年、2015年和2018年土地利用类型数据,选择多样性、丰富度、均匀度和优势度4个测算指标,分别测算各期生物多样性指数及时空格局,运用OLS回归和分位点回归评价"百万亩"造林对浅山区生物多样性的影响方向和程度。[结果](1)2018年北京市浅山区林地覆盖率达到51.66%,林地面积较2015年增加了3 400hm~2,且林地二级类型间变化较大;(2)2018年北京市浅山区多样性指数、丰富度指数、均匀度指数和优势度指数均值分别为0.432、0.544、0.504和0.276,多样性和均匀度有小幅度降低,但丰富度和优势度提升明显。(3)不同分位水平下,人工造林对浅山区生物多样性的影响方向和程度并不一致,在10%分位水平下,样本单元内林地面积的快速增加均对各项生物多样性指数有显著的促进作用,但影响程度不同。[结论]人工造林应综合考虑源地物种分布状况、造林类型和优势林种等多方面因素,才能最大程度发挥其对生物多样性的修复和保护作用。  相似文献   

17.
In Europe, the active contribution of farmers to nature conservation is mainly voluntary. Whereas participation in agri-environmental schemes (AES) has been studied in detail, less is known about self-initiated nature conservation. Given the alarming decline in species diversity and abundance in agricultural landscapes, it is important to explore this form of conservation in more detail. In this paper we report on the results of a survey of Dutch dairy and arable farmers. We conclude that a large majority of farmers conduct self-initiated conservation activities on their farmyards and fields with varying ecological impacts and impacts on farming system. Helping birds was the most often mentioned activity. Farm size, on-farm side activities (in dairy farming), organic farming, the quality of the surrounding area and the absence of external constraints have a positive effect on the number of activities. Intensity has a negative effect on both the number of activities and on the probability that farmers conduct activities with substantial ecological impacts. There is no unambiguous evidence of a ‘crowding-out effect’ due to participation in AES. More research in this area can help contributing to a maximal exploitation of the conservation potential by farmers and to creating synergies with agri-environmental policies.  相似文献   

18.
Managing agricultural floodplains to meet present and future human requirements without jeopardizing biodiversity conservation is a challenge for land use planners and ecologists. This paper aims to disentangle the relationships between ecosystem services and biodiversity in multifunctional landscapes, such as floodplain agroecosystems, by disaggregating their values across land use types. We measured eight ecosystem services (gas regulation, soil formation, nutrient regulation, habitat provision, food provision, raw materials production, education, and recreation) and six plant diversity indexes (richness, abundance, and true diversity for both plant species and growth forms) in seven land use types identified in the floodplain of the River Piedra (Spain). We observed that all land use types provided services to some extent, but each one was better at providing certain services. Natural or semi-natural habitats provided more services and hosted greater diversity than cultivated land use types. In addition, five diversity indexes were strongly correlated to at least three ecosystem services each one. Habitat provision and education were the ecosystem services positively correlating to most diversity indexes, whereas food provision was negatively correlated to all diversity indexes. Moreover, analyzing the interactions between ecosystem services and biodiversity across land use types, we observed that land use type was the controlling factor regarding the sign and significance of the interaction. The results of this study suggest that, in floodplains agroecosystems, a mosaic landscape of different land use types helps support ecosystem services and contributes to maintaining biodiversity while using local resources. Such land use policies might manage agricultural floodplains at the landscape scale while still being able to accommodate specific measures for each land use type. Moreover, riparian forests should be preserved and restored across the floodplain as they are hot spots for biodiversity and ecosystem services provision.  相似文献   

19.
This study develops a theoretical and empirical framework for optimal conservation planning using satellite land cover data and economic data from a farm survey. A case study is presented for a region within the South‐west Australia Biodiversity Hotspot (Nature 403, 853). This Biodiversity Hotspot is a focus for conservation investment as it combines a relatively high level of biodiversity with severe threat to the biodiversity from agriculture. The conservation planning model developed determines the optimal set of bush fragments for conservation. This model can also be used to assess the trade‐off between the budget and a vegetation species metric. Results from the case study show that, without an effective conservation scheme that at least fences fragments, significant plant biodiversity losses will occur in the North East Wheatbelt Regional Organisation of Councils region of the WA wheatbelt over a 10‐year period. A perfect price discriminating auction scheme could reduce the costs of conservation by around 17 per cent relative to a fixed‐payment scheme; however, a fixed payment on outcome (measured as change in the species metric) scheme represents a viable second‐best alternative, to a conservation auction, where conservation spending is spatially targeted.  相似文献   

20.
松嫩平原湖泊湿地植物群落多样性及其保护研究   总被引:3,自引:0,他引:3  
松嫩平原湖泊群是我国温带亚湿润地区低平原湖泊群,湖泊面积2750km2,湖泊率6%,是我国湖泊密度最大的地区之一,湖泊类型多样,有高等植物148种,隶属于38科77属;有16种植物群落,分属于挺水植物群落、浮叶植物群落、沉水植物群落、漂浮植物群落四大类;研究了松嫩平原湖泊湿地植物群落多样性现状,提出了生物多样性的保护对策;提出了相关的嫩平原湖泊湿地植物群落多样性保护对策。  相似文献   

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